I know the actual start of this thread is really old (Jan 27, 2006), but the information in the original post is key to the talk of blank adapters and his problem. I recently found an original wood blank, and thought most people had probably never seen one, so I've included a picture. Sharing is good.

He says he is using a wooden blank. This means the bullet isn't jacketed lead, it is made of wood (actual wood - like sticks and logs), which was very common for German training. The below cartridge base shows that it was made in '44.

Talking about a restricted nozzle for a wood blank is useless, as a wood blank won't shoot with a nozzle restrictor, as the wooden bullet won't make it through the small hole. It takes the two piece blank barrel to make this work.